all this guy got away with, samsung 30 x3 and $30 from the guy. just at scary, tense moment from the guy. i don't know if it's brave or stupid what this guy did in the black shirt. >> i'm hoping the gun maybe was fake he he just had the common sense not to be violent over $30 and a cell phone. >> i hope there's a clear shot of his face. >> hopefully somebody can identify this guy. >> that take as brave guy to say, i'm not going to be your victim. >>> our favorite rocket scientist mark is back. i want to point out, though, before we get into it, showing us a little love in this latest video. >> no way. >> mark rober. >> a nasa engineer, his name is mark rober. >> i create add costume that basically create add hole in my gut. >> thanks, man. >> he got more than 3 million views on it. using an expensive device, like the ipad, this time you can use your android phone or your iphone. >> people have those. >> there is an app called digital dudz that he and his buddies created where you can download and animation. you go to their website and buy the t-sh